The present invention is based on a device for measuring the pressure of a gas like medium in accordance with the type of the main claim. A closed system is known from DE-OS No. 31 26 615 with the assistance of which the pressure of a gas is measurable with a power manometer which acts on a piezoelectric element. This is a closed system, the accuracy of which depends to a high degree upon the tightness of the device and which in furtherance has only a limited measuring range corresponding to the deformability of the hydraulic intensifier. Furthermore, during the deflection of a hydraulic intensifier there is a nonlinear interrelation between electrical signal and pressure, whereby the measuring results may be impaired.